Optimal dispatch of electric vehicles performing V2G regulation

Abstract

A system, method, and computer-readable storage medium for charging management for electric vehicles performing vehicle-to-grid regulation are presented. The system includes an aggregator that communicates with the electric vehicles according to a dispatch strategy to switch charging with electric power from the electric grid. The aggregator that aggregates and manages charging of a set of electric vehicles associated with an electric grid. A dispatch controller controls switching of at least a subset of electric vehicles of the set of electric vehicles between an ON state and an OFF state at a given time by sending binary charge commands to the subset of batteries, in a manner that change of charging rate of individual batteries is minimized while maintaining charging fairness among the respective electric vehicles.

What is claimed is: 
     
       1. A system, comprising:
 a processor, coupled to a memory, that executes executable program code, comprising: 
 an aggregator that aggregates and manages charging of a set of batteries associated with an electric grid; and 
 a dispatch controller that controls switching of at least a subset of batteries of the set of batteries between an ON state and an OFF state at a given time by sending binary charge commands to the subset of batteries, in a manner that change of charging rate of individual batteries is minimized while maintaining charging fairness among the respective batteries in the set of batteries, 
 wherein the set of batteries is a set of rechargeable vehicle batteries contained in a respective set of electric vehicles (EVs), 
 wherein the aggregator determines charging schedules a day ahead for each of the set of vehicle batteries of the EVs, wherein the charging fairness of each EV is a weighted fairness, and 
 wherein the dispatch controller dynamically modifies the weighted fairness by dividing the weighted fairness associated with EVs of the set of EVs that exceed their scheduled charge by a constant factor in order to decrease the respective weighted fairness. 
 
     
     
       2. The system of  claim 1 , wherein the charging fairness is maintained by dynamically modifying a fairness value such that dispatch priority is increased among the set of EVs that have not reached their charging targets. 
     
     
       3. The system of  claim 1 , wherein the set of batteries are contained in plug-in electric vehicles that are plugged into charging stations, wherein the dispatch controller controls the switching by sending the binary charging commands to a subset of the charging stations. 
     
     
       4. The system of  claim 1 , wherein the aggregator manages charging of the set of EVs by sending the binary charging commands to the EVs in which it is determined that a change in charging rate is required. 
     
     
       5. The system of  claim 4 , wherein the determination that a change in charging rate is required is determined each time a regulation command signal is received. 
     
     
       6. The system of  claim 5 , wherein the regulation command signal is received in the range of every 2 to 6 seconds. 
     
     
       7. A method, comprising:
 a processor, coupled to a memory, that executes of executable program code, comprising: 
 aggregating charging, by a system including at least one processor, a set of batteries associated with an electric grid; and 
 controlling, by the system, switching of at least a subset of batteries of the set of batteries between an ON state and an OFF state at a given time by sending binary charge commands to the subset of batteries, in a manner that change of charging rate of individual batteries is minimized while maintaining charging fairness among the respective batteries in the set of batteries, 
 wherein the aggregating charging of the set of batteries includes aggregating charging of a set of chargeable vehicle batteries contained in a respective set of electric vehicles (EVs), 
 wherein the aggregating includes determining charging schedules a day ahead for each of the set of vehicle batteries of the EVs, and 
 wherein the charging fairness of each EV is a weighted fairness, 
 the method further comprising dynamically modifying the weighted fairness by dividing the weighted fairness associated with EVs of the set of EVs that exceed their scheduled charge by a constant factor in order to decrease the respective weighted fairness. 
 
     
     
       8. The method of  claim 7 , wherein the charging fairness is maintained by dynamically modifying a fairness value such that dispatch priority is increased among the set of EVs that have not reached their charging targets. 
     
     
       9. The method of  claim 7 , wherein the set of batteries are contained in plug-in electric vehicles that are plugged into charging stations, wherein the controlling includes sending the binary charging commands to a subset of the charging stations. 
     
     
       10. The method of  claim 7 , wherein the aggregating charging of the set of EVs includes sending the binary charging commands to the EVs in which it is determined that a change in charging rate is required. 
     
     
       11. The method of  claim 10 , wherein the determination that a change in charging rate is required is determined each time a regulation command signal is received. 
     
     
       12. The method of  claim 11 , wherein the regulation command signal is received in the range of every 2 to 6 seconds. 
     
     
       13. A non-transitory computer-readable storage medium storing computer-executable instructions that, in response to execution, cause a system including at least one processor to perform operations, comprising:
 aggregating charging a set of batteries associated with an electric grid; and 
 controlling switching of at least a subset of batteries of the set of batteries between an ON state and an OFF state at a given time by sending binary charge commands to the subset of batteries, in a manner that change of charging rate of individual batteries is minimized while maintaining charging fairness among the respective batteries in the set of batteries, 
 wherein the aggregating charging of the set of batteries includes aggregating charging of a set of chargeable vehicle batteries contained in a respective set of electric vehicles (EVs), 
 wherein the aggregating includes determining charging schedules a day ahead for each of the set of vehicle batteries of the EVs, and 
 wherein the charging fairness of each EV is a weighted fairness, 
 the operations further comprising dynamically modifying the weighted fairness by dividing the weighted fairness associated with EVs of the set of EVs that exceed their scheduled charge by a constant factor in order to decrease the respective weighted fairness.